LeafDD - Dash Display for Leaf

[timba33]

Hello,
I'm pretty confused with the numbers coming out of the leaf as portrayed by the Leaf DD.
Tonight it shows 80% health at 59.73 Ah. Just a couple of weeks ago it showed 91% health at 62.97 Ah.
Something is wonky.

Most of these values have been derived by smart people doing reverse engineering, unfortunately the "H" value, commonly called "Health" is probably only related to actual battery "health" in a convoluted way. It would much better be called "H-factor" until it is better understood. However the name "Health" for this value has become entrenched and won't likely change.

Well before we had the P3227 update and I had just a half dozen vehicles worth of data it seemed to track capacity as a percentage so for lack of a better word I called it "Health". "Health" of course could mean all kinds of things.. For the moment TickTock and I have decided just to call it Hx. Still... going from 63Ah (222Gids @80%) down to 59.7Ah (210Gids @80%) over such a short time is rather alarming.

OK, I have a question/concern. I have a 2013 leaf, purchased in June (sticker says manufactured 5/13), and according to LeafDD my Ah number (C value on screen 2) is 58. After reading through this thread, I should be in the 60's. Is there something going on with my Leaf? I just charged to 100% last night, and the S number (SOC?) shows 97%, GID's show 254. Is this low for a new leaf? I typically only charge to 80%, but do charge to 100% once a month or so. On my longest drives, with 100% charge , I have gone about 65 miles with about 20 miles that remain on the GOM. This includes about 25 miles freeway at 60-65, so I don't think I have any issues with capacity. I'm just curious why the "C" number appears to be much lower than this thread suggests for a new 2013 Leaf.

Thanks in advance to the experts in the forum !!!

-Tim

See LeafDD pics below.

 

[GregH]

Yeah.. 58Ah/254Gids seems low for a new 2013 Leaf with 3032 miles on it, driving in coastal Southern California..
I'm in Irvine and my 11 month old 2012 with 15k miles is around 61Ah and charges to 255-260 Gids.
A while back I had a 2013 rental from Tustin Nissan that had amazing capacity.. 284 Gids, 67.3620A, Hx was 110% !! I'll be at the dealership tomorrow to deal with my funky OBC issues.. I'll see if I can find that dealer car and check the manufacture date... and check the capacity.

 

[Stoaty]

OK, I have a question/concern. I have a 2013 leaf, purchased in June (sticker says manufactured 5/13), and according to LeafDD my Ah number (C value on screen 2) is 58. After reading through this thread, I should be in the 60's. Is there something going on with my Leaf?

There have been a number of reports of significantly lower Ah readings for 2013 Leafs, which sometimes increase over a month or two. So far the reports seem to indicate that the range is normal, but the capacity reads low.

 

[timba33]

Thanks, I wanted to check with the experts here.

My range is fine. No issues with that.

The Ah #'s and 100% charge GIDs from LeafDD (shown above in prior post) don't match what others have posted for their Leafs, so it appears there is something a bit different being reported by my 2013 model. I will assume that Nissan has done something to hold back some reported capacity and is being overly conservative in some of its capacity numbers.

Today, I drove (city driving with 3 stops) 23.2 miles starting with 100% charge, and the reported SOC from the Leaf display went from 100% to 71% , GOM miles went from 83 (full) to showing 59 miles capacity, with 9 bars. LeafDD shows SOC went from 97% down to 71.8%, and GIDs at start were 254, and now 178.

So, I used approx 26% of battery. I should be able to squeeze 70-80 miles of city driving before it gets close to zero on the GOM. Sounds about right.

I can live with that.

 

[GregH]

Your Leaf with 58Ah charging to 97% is probably similar to mine with 61Ah but only charging "full" to 92%.. In the end the Gids show it.. I end up around 254 Gids as well. As long as the range works for you there's probably no point in stressing over the numbers. Even though I only have 70-75 miles of real range, I only need about 50 miles a day. Heck now that my L1 EVSE charges at 1.5kW I'm getting a full charge every night just on 120V. Not that I prefer that over a functioning 3.3kW OBC, but I could live with it.

 

[ranss12]

So I've had the LEAFDD since early November and really like it.
One thing I've noticed is that battery temp sensors 1 and 2 always read much higher than 3 and 4 - as much as 4.0C higher. Does everyone's 1 and 2 read high? In the summer, do these still read higher?
On my 30 mile morning commute, the battery temp reading is typically between 36F and 40F even when the outside temperature is 7F. Even with this 30F differential between battery temp and ambient temperature, the battery temperature doesn't drop during the 1 hour commute. Presumably this temperature differential reverses in the summer, because even on the few days it reached 90F here I never saw 7 temperture bars. Anyone else notice this?

 

[GregH]

Yeah, my temp#1 and #2 are almost always higher unless the car has been sitting in the shade for many hours. It's odd because best I can tell the temp sensors in the wiring harness plug into the back side of the modules.. same way for all 4 (or 3 on a 2013). So why would a DCQC session heat up #1 and #2 more if all the temp increase is coming from the high current? Shouldn't it be the same on all cells? Sometimes when the car is in the sun I wonder if warming of the chassis on one side or the other produces a slightly higher reading. I think #1 and #2 are in the rear pack under the back seat (cells oriented vertically).. Whereas the others are on the horizontal forward modules.. I am impressed with how little the pack heats while driving. During my morning commute (50-60F.. I know, tough here in California) usually the temp barely budges save for a few hills near the end of the drive.. I figure the ambient air cooling offsets the IR losses at moderate speeds with about a 10-20F differential from ambient to pack temp.

 

[Stanton]

FWIW, I've noticed the differential (between 1/2 and 3/4) is smaller during the (hot here) summers than in the winters. As Greg has pointed out before, it must have something to do with the proximity to the control module (or somesuch) that's feeding/bleeding the cell pairs. That's why I sometimes see 7TB briefly in the summer drop back down to 6TB on my way home; not saying that it's good for the battery, but the LeafDD verifies that we're not talking about REALLY high temps (like 110 degree+).

 

[GregH]

BTW.. Any of you folks in the colder climates like ranss12.. I'd be curious how close the LeafDD tracks true pack temps down that low.
The car only reports a whole number in degrees C as well as a raw A/D value which has nearly 10x the precision (more so at cold temps, less so at hot temps due to the nature of the thermistors). LeafDD tries to calculate an extra digit of precision based on the raw A/D values but in the really hot and cold climates, my pseudo logarithmic software might be off a tad. If on page 2 you see a little + or - next to the temp, it means the whole number temp didn't match the whole number temp that LeafDD calculated. (press and hold the button on page 2 to see the alternate page with the car's estimation of temperature and the raw A/D values).
If someone could report the LeafDD vs. Leaf temp + raw A/D for a few temps I'd be curious to see it (see an example on the first post of this thread)
I had been keeping a public log of the conversion values on the "active CAN sampling thread" but haven't touched it in a while..

http://www.mynissanleaf.com/viewtopic.php?f=44&t=11676

Thanks!

 

[NeoFuture]

Im interested in testing this here is the chilly heights of UK winter time, i may order one from you when i can better afford it having only had my LEAF for 3 weeks

 

[GregH]

Special thanks to Sean W., Tom F., Alain C., Stuart G., Greg S., Tomasz K., Steve W., Brian M., and Jonathan B. for helping dig up temperature calibration data down to 0C (32F) and beyond!

I'm happy to confirm the original LeafDD software is accurate down to 0.0C (32F)

Unfortunately though as many (above included) have noted, LeafDD doesn't report below 0C (32F). Mostly because I didn't want to make assumptions about the non linearity of the thermistor response without hard data... and living in SoCal it's hard to get that data myself!

We can now confirm that 0.0C (32.0F) is 720 on the raw (alternate page 2 temps.. hold down the button to toggle)
Given the trend in the 0-10C range one might assume the trend of 0.1C per RAW step might continue into the negatives even though that seems unlikely given what I know about thermistors.. but perhaps the Leaf itself is sloppy in its temperature translation and at the end of the day what really counts is not the true temperature, but what the Leaf THINKS the true temperature is.

If this trend continues, you could use: temp (degrees C) = -(RAW-720)/10
ie if you see 750 that would be -3.0C or 26.6F...

The Leaf reports negative temperatures as negative 8 bit signed values which means -1C is 255, -2C is 254. The LeafDD sees this as unsigned and just displays 99 on the alt page (this is why negative numbers show 0.0+ on the normal page 2.. The LeafDD computes 0, but sees 255 for the Leaf's calculated value so assumes we are too low when in fact it's the opposite).

I'll fix the 99 issue (and the +/-) on the next rev going out this week and perhaps some of the new customers in CT and VA can confirm numbers below 0C.

If there are others that want updates for the cold temps (or anything else, like Brusa control or impedance testing.. added later) I will reflash your unit for free but cannot afford to pay shipping.. This is a hobby for me, not a business. In the U.S. it's $5.80 for domestic priority small box shipping... anyway, we'll figure out something.

But in the meantime, -(RAW-720)/10 could give you accurate temps below 0.0C if the 0.1C/step thing holds.
Alain C. saw 826!!! Could this be -10.6C?? Brrr...

As I noted to Sean btw, this is NOT a competition!!

 

[wsbsteven]

No problem Greg, I'll send mine out sometime this year for updates but I'll wait for this cold weather to pass first.

 

[lion]

Is there anyway we can flash it ourselves? I have the cable run into the dashboard, and really don't want to take it apart, as the cable is now stuck in that position thanks to this cold.

 

[GregH]

LeafDD is based on a Silicon Labs 8051 8bit micro.. (C8051F560) I used a $40 Silabs USB dongle to flash the units using their proprietary C2 protocol (only really needs two of the pins, unlike full JTAG). I don't know if the freeware version of their IDE can receive an object file and flash the chip from it, or if it's limited in file size. I know the freeware version of the compiler only does small files. I paid $1000 for the full compiler 8 years ago.

I guess that's the long answer..

Short answer, probably not worthwhile trying to re-flash in place.

For those willing to mail back the LeafDD and provide the prepaid shipping label for the return, I'm willing to re-flash and repackage/ship for free..
I think it's $5.80 each way US Priority mail in the free USPS small boxes that I use to ship.

All that being said, the latest software doesn't really add many new features from the V1.1.1 software. Namely support for an additional Brusa 3.3kW charger under the hood for '11/12 Leafs, ability to calculate battery pack impedance (could be done manually by watching the voltage and current on Page 2 at rest vs. hard acceleration), or the ability to see battery temperatures below 0C (32F) (although this also could be calculated manually from the alt page 2 raw temperatures once we have a good picture of the relationship between raw A/D values and degrees C below 0).

If you'd still like the update, contact me offline at [email protected]

P.S. We're up to about 108 units shipped with 40 or so more to go. I won't be producing any more after that.

 

[Stoaty]

If there are others that want updates for the cold temps (or anything else, like Brusa control or impedance testing.. added later) I will reflash your unit for free but cannot afford to pay shipping.. This is a hobby for me, not a business. In the U.S. it's $5.80 for domestic priority small box shipping... anyway, we'll figure out something.

Thanks for the offer, but the LeafDD is already perfect for me. My favorite Gid meter of all time. Thanks for designing, producing and selling it at such a reasonable price!!!

 

[glecko]

If you'd still like the update, contact me offline at [email protected]

P.S. We're up to about 108 units shipped with 40 or so more to go. I won't be producing any more after that.

Dang, does that mean I'm not able to order a unit? Sorry if I misread your statement, I'll email you separately. Sounds like a really handy monitor/tool.

 

[Stanton]

If there are others that want updates for the cold temps (or anything else, like Brusa control or impedance testing.. added later) I will reflash your unit for free but cannot afford to pay shipping.. This is a hobby for me, not a business. In the U.S. it's $5.80 for domestic priority small box shipping... anyway, we'll figure out something.

Thanks for the offer, but the LeafDD is already perfect for me. My favorite Gid meter of all time. Thanks for designing, producing and selling it at such a reasonable price!!!

I'll second that comment...and I have unit #8!

 

[lion]

LeafDD is based on a Silicon Labs 8051 8bit micro.. (C8051F560) I used a $40 Silabs USB dongle to flash the units using their proprietary C2 protocol (only really needs two of the pins, unlike full JTAG). I don't know if the freeware version of their IDE can receive an object file and flash the chip from it, or if it's limited in file size. I know the freeware version of the compiler only does small files. I paid $1000 for the full compiler 8 years ago.

I guess that's the long answer..

Short answer, probably not worthwhile trying to re-flash in place.

For those willing to mail back the LeafDD and provide the prepaid shipping label for the return, I'm willing to re-flash and repackage/ship for free..
I think it's $5.80 each way US Priority mail in the free USPS small boxes that I use to ship.

All that being said, the latest software doesn't really add many new features from the V1.1.1 software. Namely support for an additional Brusa 3.3kW charger under the hood for '11/12 Leafs, ability to calculate battery pack impedance (could be done manually by watching the voltage and current on Page 2 at rest vs. hard acceleration), or the ability to see battery temperatures below 0C (32F) (although this also could be calculated manually from the alt page 2 raw temperatures once we have a good picture of the relationship between raw A/D values and degrees C below 0).

If you'd still like the update, contact me offline at [email protected]

P.S. We're up to about 108 units shipped with 40 or so more to go. I won't be producing any more after that.

I'm guessing updating it myself is not an option

The main feature I need is the below-freezing temp reading. I wasn't aware of this temp issue, so it kinda screwed up my data collection I've been doing.

I'm a little worried about screwing around with the dashboard/cabling when it's this cold, so I won't be able to send it in for another month or so.

 

[GregH]

The main feature I need is the below-freezing temp reading. I wasn't aware of this temp issue, so it kinda screwed up my data collection I've been doing.

If you're collecting data, on page 2 hold down the button to switch to the "raw" numbers. If the temp goes negative (Celsius) then it will say 99|xxx.. log those xxx numbers as that's the raw A/D from the Leaf temp sensors. Hopefully in the future I'll have an exact translation of what xxx = in degrees C (or F).

The latest software (V1.3.1) does show the actual temp below 0C.

Thanks for the kind words guys! I ordered 150 PCBs a year ago and I think I have enough plastic shells to make about 145 or so (several failed test and I haven't gone back to rework them).. Today shipping out #114 and I've got #115 and #116 boxed and sitting in the car waiting for orders. After this I believe about 29 more will be produced. At the current rate that should mean availability through April.

 

[jlsoaz]

Hi

I ordered one of these recently and just noting that it seems to be functioning well, easy install for the non-technical person like myself, not too expensive, and easy ordering/delivery process.

Josh